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anonymous
 4 years ago
(cos A + cos b)^2 + (sin A + sin B)^2=?
anonymous
 4 years ago
(cos A + cos b)^2 + (sin A + sin B)^2=?

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anonymous
 4 years ago
Best ResponseYou've already chosen the best response.0@apoorvk @satellite73 @A.Avinash_Goutham @ajprincess @AndrewNJ

anonymous
 4 years ago
Best ResponseYou've already chosen the best response.0okay, expand the two wholesquares, it's simple enough...

anonymous
 4 years ago
Best ResponseYou've already chosen the best response.0the options are 4cos^2(ab/2) 4 sin a/2 cos b/2

anonymous
 4 years ago
Best ResponseYou've already chosen the best response.0dw:1339426035616:dw

anonymous
 4 years ago
Best ResponseYou've already chosen the best response.0@apoorvk after expanding i got this then next..............

anonymous
 4 years ago
Best ResponseYou've already chosen the best response.0great, now.. cosAcosB + sinAsinB = cos(AB) Use this^

anonymous
 4 years ago
Best ResponseYou've already chosen the best response.0ugh, trig identities are a drag. Even after deriving them myself I simply CANNOT seem to memorize them

anonymous
 4 years ago
Best ResponseYou've already chosen the best response.0spread it so we have (cosa)^2+(cosb)^2+2(cosa)(cosb)+(sina)^2+(sinb)^2+2(sina)(sinb) =2+2cos(ab)

anonymous
 4 years ago
Best ResponseYou've already chosen the best response.0(cosa)^2+(sina)^2=1 (cosb)^2+(sinb)^2=1 (cosa)(cosb)+(sina)(sinb)=cos(ab)

anonymous
 4 years ago
Best ResponseYou've already chosen the best response.0ok @apoorvk so it is not over yet!!@

anonymous
 4 years ago
Best ResponseYou've already chosen the best response.0Continuing from where @AndrewNJ left, \[2(1+\cos(ab))\] now we know that \[1 + \cos 2a = 2 \cos^2 a\] Now try :D

anonymous
 4 years ago
Best ResponseYou've already chosen the best response.0@shivam_bhalla did nt understand!

anonymous
 4 years ago
Best ResponseYou've already chosen the best response.0= \[2(1+\cos 2\frac{(ab)}{2})\] Now we have a identity, \[1 + \cos 2x = 2 \cos^2 x\] in your case, \[x = \frac{ab}{2}\] Now try

anonymous
 4 years ago
Best ResponseYou've already chosen the best response.0i got it thxx @shivam_bhalla

anonymous
 4 years ago
Best ResponseYou've already chosen the best response.0@shivam_bhalla plzz help http://openstudy.com/study?signup#/updates/4fd60c0be4b04bec7f170b7d
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